Refrigerating apparatus



p '1940? F. l. RATAICZAK 2,214,086

REFRIGERATING APPARATUS Filed Dec. 51; 1938 2 Sheets-Sheet l 27: 9:INVEN'FOR.

flzmvcls [BOT/71:38AM

l/I ATTORNEYS.

. Sept. 10, .1940.

F. 1. RATAICZ'AK REFRIGERATING. APPARATUS Filed Dec. 31, 71938 2Sheets-Sheet 2 INVENTOR. Ewvc/s 1 F4 rnlrZA A,

l/IS ATTORNEYS Patented Sept; 10,'

- UNITED STATES 2,214,086 'BEFRIGERATING APPARATUS Francis 1. Rataiczak,Dayton, Ohio, assignor to General Motors Corporation, Dayton, Ohio, a

corporation of Delaware Application December 31, 1938, Serial No.248,888

- 12 Claims.

My invention relates tocompressor units and particularly to hermeticallysealed motor-compressor units embodying a rotary compressor.

The efiiciency of a rotary compressor depends in part upon the clearancebetween the cylinder walls and the rotating elements or equivalentdevices. This clearance varies as the temperature of the unit varies.Thus, a clearance which is proper to permit the starting of the rotarycompressor may decrease to such an extent as the temperature of the unitincreases as to cause a binding of the moving parts. On the other hand,a clearance calculated to produce emcient operation at hightemperatures, may be so excessive at low temperatures as to prevent thecompressor from. picking up the load placed thereupon.

In small units such as have been employed commercially on a very largescale to produce refrigeration in a household refrigerator cabinet, thisproblem is not critical because the volume of refrigerant worked by theunits is not of such intensity as to cause excessive heating within theunit, and fins attached to the exterior wall of the casing of thesesmall units ordinarily sufiice to dissipate heat therefrom. As thecapacity of a unit is increased to meet the requirement of refrigeratinglarger areas or spaces, these larger units have greater internal heatloss and it becomes increasingly more diflicult' to withdraw heatthrough the structure. For this reason, commercial use of rotarycompressor units of the hermetically sealed type has been limited tosmall units because it has been impossible to properly prevent a largevariation in clearance between parts of the larger units.

I overcome these problems in a large rotary compressor unit byconstructing the various parts thereof, wherever possible, of metalshaving the same coefi'icient of expansion and contraction and byproviding rapid conduction of heat from the internal parts to theprimary cooling means.

An object of the present invention is to provide an improved sealed unitcompressor construction.

substantially constant tolerances between the parts.

PATENT orrlce Another object of the invention is to utilize refrigerantcontained in a closed refrigerating system having a hermetically sealedmotor-compressor unit forming a part thereof for removing heat from themotor rotor, the main bearing of the unit and parts of the compressor inthermal contact therewith to thereby cool and maintain same atsubstantially a uniform temperature particularly at times during whichan abnormal amount of heat is generated.

In carrying out the foregoing objects, it is a further and more specificobject of my invention to provide an improved construction for andmethod of utilizing the flow of compressed refrigerant discharged from acompressor in 2. hermetically sealed motor-compressor unit to withdraw asmall amount of condensed liquid refrig- "erant'irom its storagereservoir, to circulate the withdrawn liquefied refrigerant along withthe compressed refrigerant in thermal heat exchange relation withelements located centrally of the unit and to evaporate the liquidrefrigerant during its circulation with the compressed refrigerant forremoving heat from the centrally located elements and transferring thisabsorbed heat to the primary cooling means of the sealed unit.

Still further objects reside in details of con- .struction and in novelcombinations, arrangements and cooperation of parts of the structure toprovide a novel and improved sealed motorcompressor unit as will morefully appear in the course of the following description.

In the drawings in which like characters designate similar partsthroughout the several views:

Fig. 1 is a vertical sectional view of a 'motorcompressor-condenser imittaken on the line i-l of Fig. 2 and constructed in accordance with thepresent invention;

Fig. 2 is a horizontal sectional view through the 40 unit shown in Fig.1 and is taken on the line 22 thereof; and

Fig. 3 is a fragmentary sectional View taken on the line 3-3 of Fig. 1showing the condenser structure.

Referring to the drawings, Fig. 1 shows a her metically sealed'unitcomprising a motor, a compressor and a condenser. These elements of thesealed unit form part of a conventional closed refrigerating systemwhich system also includes an evaporator and an expansion or the likevalveor device (not shown) for controlling the flow of refrigerant fromthe unit to the evaporator. The unit, generally represented by thereference character 10, includes a lower metal housing H providing anoil sump'or reservoir and having an outwardly directed annular flange I2formed on its top extremity. A dome, generally represented by thereference character I4, comprises a heavy metal ring I5, acylindrical'member I6 and a cap member I1 all welded or otherwisesuitably secured together. The dome I4 is mounted upon the lower housingII by a plurality of bolts I8 which pass through flange I2 and arescrewthreaded into the ring I5. The cap I1 is provided with a box-likedevice which forms av juncture for electrical connections leading to andfrom the interior of the sealed unit. A plurality of metal fins I9 arevertically arranged in spaced apart relation around the interior of domeI4 and are welded or otherwise suitably secured to the inner wallsurface of cylinder member I6 (see Fig. 3) for a purpose to behereinafter described. The fins I9 are each corrugated as at 2I so thatthe corrugations are staggered and vertically inclined and each fin I9also has a flanged portion 22 which spaces the fins apart and which isse-' cured to the wall I6. A metal spider or the like member 24 having abearing portion 26 and an upstanding cylindrical wall portion 21 isprovided with a flange 28 which is secured to the flange I2 on housingII by bolts'29. The cylindrical wall portion 21 of member 24 carries astator 3|. A hollow member 32 constituting a rotor chamber 33 (see'Fig.2) is mounted, such as by bolts 34, upon the lower face of member 24.: Alower bearing member 35 is provided with a flange 36 whichis secured tothe hollow rotor chamber forming member 32 by bolts 31. There is a cap4| secured by screws 42 to the lower end of bearing member 35, and thiscap has an.opening 43 therein. A spring 44, located within cap 4|, bearsagainst a ring 45 which abuts the lower end of a shaft 46. Shaft 46extends through the lower bearing member 35, rotor chamber 33 and mainbearing portion 260i the spider member 24 and projects upwardly ofmember 24 to provide a mounting for a rotor structure 48. The rotorstructure 48 includes a hub or core 49 fitting over the upperend ofshaft 46 and provided with one or more openings 5| therethrough. Rotorstructure 48 is secured to: shaft 46 for rotation therewith by a key 52and a bolt 53. The stator 3| together with the rotor structure 48 formsan electric motor for driving the compressor of unit I6 through themedium of shaft 46.

' The compressor rotor 55 located within the rotor chamber 33 (see Fig.2) is keyed to shaft 46 by pins 56 passing through the shaft andabutting blades 51 mounted in slots provided therefor in'the rotor 55.Each blade 51 has a sealing'or rubbing block 58 associated therewith andengaging the inner wall of the hollow member 32 which forms thecompressor rotor cnamber 33. It will be noted that the compressor orpump part of unit I9 includes four blades 51 with two pins 56 disposedone' above the other between two of the blades'and that the dimensionover the pins 56 and their associated blades and sealing or rubbingblocks is predetermined or fixed. The compressor rotor 55 is concentricwith shaft 46 while the wall of rotor chamber 33 formed by member 32 iseccentric relative to shaft 46 and rotor 55. Since the distance from theface of one block 58 to the face of its associated block is fixed,rotation of rotor 55 within the eccentric chamber 33 will cause the pins56, blades 51 and blocks 58 to reciprocate within the slots provided'inthe rotor 55. The space between rotor 55 and the wall of ch mber 33,inbetween adjacent blocks 58, thus forms suction and compressionchambers for the refrigerant pump or compressor during rotation of andin accordance with the position of rotor 55 relative to refrigerantinlet and outlet ports.

- Low pressure or gaseous refrigerant flowing from the evaporator of therefrigerating system is directed through a pipe 6| and a conduitfitting, generally represented by the reference character 62 anddetachably secured to unit I8, to the compressor. The conduit fitting 62includes a pipe portion 63 positioned in a bore 64 provided in a wall ofthe hollow rotor chamber-forming member .32. An enlarged annular portion65 formed on the fitting 62 is located within an opening 66 provided inthe wall of the lower housing II. A flanged portion 61 of fitting 62abuts the wall of housing I I and receives bolts 68 which arescrew-threaded into housing II to detachably secure the conduit fitting62 to the unit Ill. A gasket or the like 69 maybe placed under .theflange 61 of fitting 62 to seal the joint between the conduit. fittingand the housing I I. In

, order to seal the joint of pipe portion 63 of fitting 62 with the bore64, I provide a resilient gasket or the like 12 which is pressedinto acounter bore 13 provided around the bore 64 in member 32. A metal washer14 is placed in back of the gasket 12 and a spring 16 is compressedbetween the enlarged annular portion 65 of fitting 62 and the washer 14.The tension of spring 16 compresses the resilient gasket 12 against thewall of counter bore 13 and against the outer wall surface of the pipeportion 63 of fitting .62 to seal the pipe portion 63 within the bore64.18 is secured within the fitting 62 to prevent the V entrance of foreignmatter into the rotor chambr 33. After other various parts of unit IIIare assembled the pipe portion 63 -of fitting 62 together with thegasket 12, washer 14 and spring A cone-shaped screen 16 surrounding sameare inserted through opening 66' in housing II and the inner end of thepipe portion 63 is pushed into the bore 64 of member 32 to therebycompress spring 16 and cause the gasket 12 to seal the joint of thefitting 62 with the bore 64. The bolts 68 are then threaded in place-tosecure the fitting 62 upon the unit I0 and to thereby cause gasket 69 toseal the joint of fitting 62 with the housing II.

The hollow member 32, forming the rotor chamber 33, is provided with anoutwardly projecting portion 8| to which a plate 82 is seemed; The innerpart of the projecting portion 8| is hollowed out and the plate 82in-cooperation with this hollowed out part of the projecting portion 8|forms a discharge chamber 83 for receiving refrigerant compressed anddischarged by the compressor of the unit II]. An opening or a pluralityof openings 84 drilled through the wall of portion 8| communicates withthe rotor chamber 33. Each of the discharge ports or openings 84 iscovered by a valve 85 secured by screws 86 (see Fig. 2) to a wall ofchamber 83. A valve backing member or protector 81 is located over thevalve 85 and is also secured by the screws 86 to member 32. A verticalopening 92 extends through a wall of chamber 33 to the upper, outer faceof member 32 (see Fig. 1). An angularly disposed hole 93 drilled throughthe bearing portion 26 inafter more fully described. The Venturi devicewall portion 21 with the body bearing formingportion 25 thereof adjacentthe hole 93 is provided with a small hole 95 which communicates at itsone end with hole 93 and at its other end=with a liquid refrigerantchamber or condenser 91 in which the fins 19 are mounted. A connector 98which communicates with the condensed refrigerant chamber or reservoir91 is adapted to have a pipe, which conveys. refrigerant liquefied bythe unit 10 to an evaporator of the refrigerating system, securedthereto. A port H (see Fig. 2) is drilled through a wall of the bottombearing member 35 and a part of this port communicates with the interiorof rotor chamber 33. i0! is normally closed by a valve 02 having a valvebacking member 103 thereover and secured to member 35 by screws I04.Valve 32 and member 103 may be of substantially the same type or designas the valve 35 and the member 8'1. The purpose of port l D! and itsclosure valve Hi2 will become apparent in the description to follow. Itwill be noted that oil contained within the oil sump formed by the lowerhousing ii is in open communication with the dome chamber formed by themember 14 through an opening or openings I08 provided in the portion ofbearing member 24 which connects same with its cylindrical portion orwall 21. The pressure externally of the rotor chamber 33' is equalizedthroughout the interior of the sealed unit, provided by dome member 14and the lower housing H, by the communicating passage or passages I06.The fitting 82, being sealed to the rotor chamber-forming member 32 andthe valve or valves 85, closes the low pressure portion of therefrigerating system from the high pressure portion thereof existingwithin the sealed unit 10.

It is to be understood that the compressor or pump part of unit 10 isimmersed or partly submerged within a body of oil in the oil sump formedby the lower housing I I. face HI formed in the spider member 24 and abearing surface H2 formed in the lower bearing member 35 for shaft. 46as well'as parts of the compressor portion of unit ID are effectivelylu-'- bricated from the body'of oil in the oil sump.

During operation of the unit l0 oil flows from the sor part of unit IDto lubricate the operating elements thereof. The oil is forced, by. theback and forth sliding movement of blades 51, into the main bearingsurface Hi and bearing surface H2 to lubricate these surfaces and entersgrooves formed in the bearing surfaces of shaft 45. The oil is caused toflow from the bearing surface II I through a passage H1, provided inmember 24, and from bearing surface 2 through a passage H8, provided inmember 35, to a point adjacent the refrigerant inlet 54 from where it isconveyed along with refrigerant around the chamber 33. Any appreciableamount or oil trapped between adjacent blocks 58 and blades 57 at thetime the rotor 55 begins to compress the refrigerant creates anexcessive pressure in the compression space between the rotor and thewall of The port A bearing surchamber 33, and this excessive pressurewill open the relief valve 102 to permit the oil to escape through theport opening lfll normally closed by the'valve 102. As soon as theabnormal pressure, caused by oil in the compression chamber, has beenrelieved valve 102 closes to cause compression of the refrigerant duringfurther rotation of the compressor rotor. Oil also flows upwardly in thehole H4 provided in shaft 46 'to the end of this hole and is thendirected through a horizontal hole H9, provided in shaft 46, to theouter surface of the shaft to lubricate the top surface of bearingportion 26 of member 24. A collar i2l bears against the lubricated topsurface of bearing portion 28 of member 24 and has a spring 122interposed between it and the hub or core 49 of motor rotor 48. Thespring 122 co: operates with spring 44, located at the lower end ofshaft 46, to maintain the shaft in the aligned position shown in thedrawings and to prevent I undue wear of parts of the unit.

the electric motor portion thereof and the shaft rotates the compressorrotor 55. Revolutions of rotor 55 within the eccentric chamber 33 ispermitted by the blades 5'! and their rubbing blocks 58 and pins 56reciprocating back and forth within their slots in the rotor. Gaseousrefrigerant evaporated in the evaporator of the refrigerating systemfiows'through the conduit fitting 82 and enters the rotor chamber 33within the space between two adjacent blades 51 of the compressor. Thisrefrigerant entering the rotor chamber is carried around the chamber,during rotation of the rotor 55 and its blades 51, into proximity withthe refrigerant outlet port 84 where v the refrigerant is compressed. Assoon'as the blade 51, in advance of another blade between which thecompressed refrigerant is trapped, passes the outlet port 84 thecompressed refrigerant is forced by the rotor out of the rotor chamber33 through valve or valves 85 into the discharge chamber 83. The spacebetween the rotor 55 and the wall of chamber 33 and between eachadiacent rotor blade 51 continues to fill with refrigerant gas drawnfrom the evaporator, to cause the evaporator to produce a refrigeratingeffect, and is compressed by rotation of therotor in the mannerdescribed while the blades 51 reciprocate within the rotor 55.

.The refrigerant compressed by the compressor and caused to enter thechamber 83 flows from chamber 83 through the passage 92 and is directedthrough the Venturi device, formed by ring 94 within passage orpassageway 93, into the passageway 93. During the flow. ofcompressedrefrigerant past or through the Venturi device or ring 94 a small-amountof previously cooled and liquefied refrigerant, from the condenserchamber 91, enters the passageway 33 by way of the small passageSB. Someof the precooled liquid refrigerant entering the passage 93 and mixingwith the compressed vaporous refrigerant immediately expands orVaporizes, and in flowing through the passageway 93 this evaporatingrefrigerant removes heat from the bearing portion 26 of the spidermember 24 and consequently cools the main bearing surface ill and partsof the compressor in intimate heat exchange relation with the bearingportion 28. The remainder of the precooled liquid refrigerant enteringpassageway 93 is discharged therefrom along with the compressedrefrigerant and in further. evaporating is caused the hub or core 49 ofmotor rotor 48. Evaporation of this remaining portion of the precooledliquid refrigerant or further evaporation of the partially evaporatedliquid refrigerant in the vicinity of the .motor rotor 48 cools rotor 58and carries the heat removed therefrom along with the compressedvaporous refrigerant upwardly above the motor rotor. The revolving motorrotor directs the vaporous refrigerant laterally therefrom over themotor stator 3| and into contact with the ends of condenser fins I9which extend above the refrigerant condensing chamber 91. As therefrigerant contacts the fins I9 it is cooled and flows downwardly overand around the fins I9 whereby it iscondensed and liquefied and drops tothe bottom of chamber 91. The condensed liquefied refrigerant is storedin chamber 91 prior to being circulated, by a pipe connected to theconnector 98, to the evaporator of the refrigerating system. It is, ofcourse, to be understood that it is a portion of this cooled andliquefied refrigerant which flows through the small passage 96 to bemixed with the compressed vaporousrefrigera'nt and to be evaporatedtherein forcarrying out the cooling process of the bearing portion 26 ofmember 24, the main bearing surface III, the motor rotor 48 andconsequently parts of the compressor in thermal contact with the bearingportion 26 of member 24 as described. A water cooling coil I3I, havingan inlet I32 and an outlet I33, is welded or otherwise suitably securedto the outer wall surface of the cylindrical wall portion I6 of domemember I4 to augment removal of heat from the refrigerant to cool andcondense -same.

Since the unit III disclosed is intended for use in large refrigeratingsystems such as, for

example, refrigerating systems of from one to five-ton refrigerationrequirements, the demand upon the unit is far greater than inrefrigeratingsystems employing a conventional small size refrigerantcompressing unit, andconsequently the present unit must be of increasedcapacity. In such large units an intense amount of heat is generated,and unless the unit is cooled internally in the manner herein disclosed,it will not be efiicient in meeting the refrigerating requirementsplaced upon it. For example, heat generated by the motor rotor 48 andtransmitted to bearing portion 29 of member 24 and/or heat generated inthe main bearing surface III and transmitted to parts of the compressormight be so intense that the bearing surface would be damaged or sointense as to cause irregular expansion of centrally located parts ofthe unit relative to other parts thereof. However, my method of removingheat from the bearing surface and from the motor rotor eliminates thepossibility of damaging the main bearing and avoids undue expansion ofcertain parts of the unit to provide a construction capable ofoperationover long periods of time; My invention permits the,constructiono acombined motorcompressor-condenser unitand provides 8. hermeticallysealed unit of compact and improved structure.

It is important in a unit of the type disclosed to control the motortemperature in direct proportion to the load placed upon the compressor.

That is, over-cooling of the motor is not desired because its,efllciency has been found to be greater when a certainpredeterminedminimum amount of heat is present therein or in thevicin'itythereof. However, an excess amount of heat within or in thevicinity of the motor under heavy load conditions must be removed sincethe heat may be rapidly conducted to the main bearing and other parts ofthe unit. Therefore, the size of the passages or passageways 92 and 93and also passage 96 relative to passages 92 and 93 and the size of ring94 is calibrated so that the volume of compressed vaporous refrigerant,flowing through passages 92 and 93 and through the Venturi device, andits velocity modifies the efiect of the Venturi device formed by thering 94-. In other words, in the structure disclosed the volume and/orvelocity of the vaporous refrigerant discharged by the compressorautomatically changes the effectiveness of the Venturi device to drawmore or less precooled condensed liquid refrigerant from the condenser91 through passage 96 and into the passage 93. Under heavy loadconditions the compressor discharges a greater amount of refrigerantthan under normal or. minimum load conditions and a greater amount ofprecooled liquid refrigerant is withdrawn, by the suction effect createdby the Venturi device, from condenser 91 through passage 96 and into thepassageway 98 to increase the cooling of the motor, the main bearing IIIand parts of the compressor during existence of the heavy loadcondition.By this increased cooling efiect I control the temperature of the motorand particularly its rotor, the main bearing and parts of the compressorin direct- Since the oil sump within housing II stantially equalized.This equalization of pressure within the unit Ill insures an efiectivecirculation of oil and efiicient lubrication of operating parts of theunit. The Venturi device forms an obstruction within passageway 93 tothe flow of refrigerant therethrough to cause a slightly greaterpressure, say for example approximately two pounds, to be built up inthe discharge chamber 83 than in the interior of the hermetically sealedunit during operation of the compressor. Obviously, this differential inpressure existing between the discharge chamber 83 and the interiorof'unit I0 is employed to render the Venturi device effective 'towithdraw liquid refrigerant from the condenser 91.

The various parts of the present unit and particularly parts of thecompressor, the housing forming the main bearing for the shaft and theshaft are composed of metal having substantially the same constituentsso that the expansion and contraction of all the cooperating parts willbe as nearly uniform as'possible. The uniform coelficient of expansionand contraction of the metal parts together with the efiectivelubrication thereof and the method of cooling the I various centrallylocated parts permits the tolthe main shaft bearing :I II both of whichmay 7 generate heat and transfer this heat to other parts of the unitare not affected by the cooling of the motor stator since they arespaced therefrom and located centrally of unit HI. Thus, it is obviousthat other means in addition to the water coil l3! must be provided forremovin heat from parts located centrally of the unit.

From the foregoing it will be apparent that I have rendered a sealedunit which normally would be ineffective for meeting large refrig-'eration requirements, capable of increased capacity, durable and oflong life even under :abnormal load conditions. In my improved unit therate of removing heat from the heat generating parts thereof is variedin accordance with loads imposed on the unit or in other words inresponse to the volume of refrigerant compressed and circulated by theunit. My invention insures increased cooling of the motor rotor and mainhearing at times when an abnormal amount of heat may be generatedthereby to thus maintain a substantially constant operating temperaturewithin the unit which is capable of preventing damage-to parts thereofand which is desirable for obtaining maximum efiiciency.

While the form of embodiment of the invention -as herein disclosed,constitutes a preferred form, it is to be understood that other formsmight be adopted. all coming within the scope of the claims whichfollow.

What is claimed is as follows:

1. In a refrigerating system including a condenser, an evaporator, ahermetically sealed unit including a compressor, a motor having a shaftconnected with the compressor for operating same and a bearing for theshaft, the method of removing heat from the shaft hearing whichcomprises, withdrawing liquid refrigerant from the condener byrefrigerant discharged from the compressor before the dischargedrefrigerant leaves the interior of the unit, circulating the withdrawnliquid refrigerant with refrigerant discharged from the compressorwithin the sealed unit and in intimate heat exchange relation with theshaft bearing to-evaporate the liquid refrigerant, and cooling andrecondensing the evaporated refrigerant.

25In a refrigerating system including a condenser, an evaporator, ahermetically sealed unit including a compressor, a motor having a shaftconnected with the compressor for operating same and a bearing for theshaft, the method of removing heat from the shaft bearing and from themotor which comprises, withdrawing liquid refrigerant from the condenserby refrigerant discharged from the compressor, circulating the withdrawnliquid refrigerant with refrigerant discharged from the compressor firstin intimate heat exchange relation with the shaft bearing and thence inintimate heat exchange relation with the motor to evaporate the liquidrefrigerant, and thereafter cooling and recondensing the evaporatedrefrigerant.

35A hermetically sealed unit comprising in combination, a casing, arefrigerant pump and an electric motor for operating the pump disposedwithin said casing', means for directing refrigerant discharged by saidpump/1n contact with said motor, means for cooling and storage means forconveying liquid refrigeranttherefrom into said directing means, andmeans rendered eifective during operation of said pump for circulatingthe liquid refrigerant conveyed into said directing means along withrefrigerant discharged from said pump and for causing evaporation of theliquid refrigerant in intimate heat exchange .relation with said motor.

4. A hermetically sealed unit comprising in combination, a casing, arefrigerant pump and an electric motor for operating the pump disposedwithin said casing, means for directing refrigerant discharged by saidpump in contact with the rotor of said motor, means for cooling andliquefying refrigerant discharged from said pump and for storing theliquefied refrigerant within said casing, means communicating with saidliquefied refrigerant storage means within said casing for conveyingliquid refrigerant therefrom into said directing means, and meansrendered effective by operation of said pump for circulating the liquidrefrigerant conveyed into said directing means along with refrigerantdischarged from said pump and for causing evaporation of the liquidrefrigerant in intimate heat exchange relation with the rotor of saidmotor.

5. Ahermetically sealed unit comprising in combination, a casing, arefrigerant pump and an electric motor for operating the pump disposedwithin said casing, a shaft connecting the rotor of said motor with saidpump, a bearing for said shaft, meansfor directing refrigerantdischarged by said pump in contact with said shaft bearing, means forcooling and liquefying refrigerant discharged from said pump and forstoring the liquefied refrigerant, means communicating with saidliquefied refrigerant storage means for conveying liquid refrigeranttherefrom into said directing means, and means rendered effective duringOperation of said pump for circulating the liquid refrigerant conveyedinto said directing means along with refrigerant discharged from saidpump and for. causing evaporation of the liquid refrigerant in intimateheat exchange relation with said shaft bearing.

6. A hermetically sealed unit comprising in combination, a casing, arefrigerant pump and,

an electric motor for operating the pump disposed within said casing, ashaft connecting the rotor of said motor with said pump, a bearing 'forsaid shaft, means for directing refrigerant discharged by said pumpin-contact with said shaft bearing and in contact with the rotor" ofsaid motor, means for cooling and liquefying refrigerant discharged fromsaid pump and for storing the liquefied refrigerant, means communicatingWith-said liquefied refrigerant storage means for conveying liquidrefrigerant therefrom into said directing means, and means renderedeffective during operation of said pump for circulating the liquidrefrigerant conveyed into said directing means along with refrigerantdischarged from said I pump and for causing evaporation of the liquidrefrigerant in intimate and the rotor of said motor.

7. A hermetically sealed unit comprising in combination, a casing, arefrigerantpump and an electric motor for operating the pump disposedwithin said casing, a shaft connecting-the rotor of said motor with saidpump, a member forming a bearing for said shaft, said member having apassageway formed therein and extending lengthwise with said shaft fordirecting refrigerant discharged by said pump along said shaft bearingand into contact with the rotor a heat exchange relation with said shaftbearing of said motor, means for cooling a'ndliquefying 75 refrigerantdischargedfrom said pump and for storing the liquefied refrigerantwithin said casing, said member also having a conduit formed thereincommunicating with said liquefied refrigerant storage means within saidcasing and with said directing passageway, a Venturi device adjacent thepoint of communication of said conduit with said passageway, saidVenturi device being rendered effective by operation of said pump forconveying liquid refrigerant from said liquid refrigerant storage meansinto said passagewaywhereby the liquid refrigerant is circulated alongwith refrigerant discharged from said pump and caused to evaporate inintimate heat exchange relation with said shaft bearing and the rotor ofsaid motor.

8. A hermetically sealed unit comprising in combination, a casing, arefrigerant compressor, an electric motor, the rotor of said motor beingmounted upon a shaft connected with the compressor for operating same, amember forming a bearing for said shaft, said motor rotor, said shaft,said bearing forming member and said compressor all being inthermalexchange relationship with one another and located. centrally of saidcasing, means for directing refrigerant discharged by said compressorthrough said bearing forming member, means for cooling and liquefyingrefrigerant discharged from said compressor and for storing theliquefied refrigerant, means communicating with liquefied refrigerantstorage means for conveying liquid refrigerant therefrom into saiddirecting means, and means rendered effective during operationof saidcompressor for circulating the liquid refrigerant conveyed into saiddirecting means along with refrigerant discharged from said compressorand for causing evaporation of the liquid refrigerant in intimate heatexchange relation with said bearing forming member to cool same and theother elements of said unit in thermal exchange relationship therewith.

9. In a refrigerating system including a conheat exchange relation withsaid one element to evaporate the liquid refrigerant, and cooling andrecondensing the evaporated refrigerant.

10. In a refrigerating system including a condenser, an evaporator, ahermetically sealed unit comprising a casing having located therein acompressor element and a motor element direct frigerant along withrefrigerant discharged from the compressor element within the casing ofthe sealed unit first in intimate heat exchange relation with the shaftbearing and thence in intimate heat exchange relation with said oneelement to evaporate the liquid refrigerant, and

thereafter cooling and recondensing the evaporated refrigerant.

11. A hermetically sealed unit comprising in combination, a casing, arefrigerant pump member and an electric motor member for operating thepump member disposed within said casing, a shaft connecting the rotor ofsaid motor member with said pump member, a bearing member for saidshaft, means for directing refrigerant discharged by said pump membertoward another of said members, means for cooling and liquefyingrefrigerant discharged from said pump member and for storing theliquefied refrigerant, means communicating with said liquefiedrefrigerant storage means for conveying liquid refrigerant therefrominto said directing means, and means rendered effective during operationof said pump member for circulating the liquid refrigerant conveyed intosaid directing'means along with re-' frigerant discharged from said pumpmember and for causing evaporation of the liquid refrig-- erant inintimate heat exchange relation with one of said members.

12. In a refrigerating system including an evaporator and a hermeticallysealed unit comprising'a casing having located therein a compressorelement, a motor element directly connected to the compressor elementfor driving same and a condenser, the method of removing heat from oneof said elements which comprises, withdrawing gaseous refrigerant fromsaid evaporator compressing same by said compressor element anddischarging the compressed refrigerant from said compressor element intosaid casing, condensing the compressed discharged refrigerant in saidcondenser within said casing and before the refrigerant leaves thecasing, withdrawing liquid refrigerant from the condenser within saidcasing by refrigerant discharged from said compressor element,circulating the liquid refrigerant withdrawn from said'condenser alongwith refrigerant discharged from said compressorelement. within thecasing and in intimate heat exchange relation with said one element toevaporate the liquid refrigerant, and cooling and recondensingtheevaporated refrigerant entirely within the casing of the sealed unit.

' FRANCIS I. -RATAICZAK.

